The 'Dog Days' of Summer are known as such because Sirius rises at about the same time as the sun.
Grand Rapids, MI (WZZM) - We are getting close to the end of what's commonly known as the 'Dog Days' of Summer.
For some answers about where that saying came from and what it means, we visited the Grand Rapids Public Museum. Surprisingly enough, this saying has been around for centuries!
Rickey Ainsworth, Planetarium Manager said, "The dog days of summer originally and still is connected to a really bright star that we see in our sky called Sirius. Sirius is the Dog Star, it's in the constellation of the dog and it's typically a star that we see in the wintertime in our evening sky. But, right now, the sun is very close to Sirius and when ancient people looked up and saw Sirius rising about the same time as the sun, they thought that Sirius' light, it's the brightest star that we can see other than the sun, Sirus' light and the light of the sun sort of combined together to make the summer heat."
Back in ancient times, Sirius rose before the sun; so observers knew it was there. Now, it rises almost simultaneously; so you can't see it with the naked eye. You'll have to wait for winter. That's when it's visible at night.